27 Search string within another string

// Q27 Search string within another string
import java.util.*;
public class Main
{
    public static void main(String[] args) {
        Scanner sc= new Scanner(System.in);
        System.out.println("Enter the exhaustive string");
        String s1 =sc.nextLine();
        System.out.println("Enter the string you want to search");
        String s2 =sc.nextLine();
        int j=0;
        for(int i=0 ; i<s1.length() ; i++){
            if(s1.charAt(i)==s2.charAt(0)){
                for(int j=0 ; j<s2.length() ; j++ ){
                    if(s1.charAt(i)!=s2.charAt(j)){
                        check = false;
                        break;
                    }
                    i++;
                }
                break;
            }
            if(s1.charAt(i)==s2.charAt(j)){
                j++;
            }
        }
        if(j>=s2.length()){
            System.out.println("First string does not contain second string");
        }
        else{
            System.out.println("First string contain second string");
        }
    }
}